Multiple channel, sequential, cardiac pacing systems

Abstract

Multi-chamber cardiac pacing systems for providing synchronous pacing to at least the two upper heart chambers or the two lower heart chambers or to three heart chambers or to all four heart chambers employing programmable conduction delay window (CDW) times timed out from paced and sensed events occurring in each heart chamber are disclosed. The synchronous pacing of one of the right and left heart chambers is provided on demand following expiration of programmable pace and sense CDWs that are started by both a paced event and a sensed event first occurring in the other of the right and left heart chambers. The delivery of the pacing pulse is inhibited by a sensed event detected in the other of the right and left heart chambers before the expiration of the corresponding CDW. In a four channel atrial and ventricular pacing system, the right and left atrial chambers are sensed and paced as necessary upon at the end of a V-A escape interval and right and left AV delays are commenced for sensing ventricular depolarizations in the right and left ventricles. The four channel system is programmable to pace and sense in three selected heart chambers.

What is claimed is: 
     
       1. A pacing system for improving the hemodynamic efficiency of a sick heart suffering from conduction delays in conducting spontaneous or evoked depolarizations originating in one of the right or left ventricle to the other of the left or right ventricle comprising: right ventricular lead means for locating first and second right ventricular pace/sense electrodes in relation with the right ventricle;   left ventricular lead means for locating first and second left ventricular pace/sense electrodes in relation with the left ventricle;   right ventricular depolarization sensing means coupled with said right ventricular lead means for sensing spontaneous cardiac depolarizations originating in the right ventricle and conducted cardiac depolarizations originating in the left ventricular from a spontaneous cardiac depolarization or delivery of a left ventricular pacing pulse to the left ventricle and for providing a right ventricular sensed event signal in response to either a sensed spontaneous or conducted cardiac depolarization;   left ventricular depolarization sensing means coupled with said left ventricular lead means for sensing spontaneous cardiac depolarizations originating in the left ventricle and conducted cardiac depolarizations originating in the right ventricular from a spontaneous cardiac depolarization or delivery of a right ventricular pacing pulse to the right ventricle and for providing a left ventricular sensed event signal in response to either a sensed spontaneous or conducted cardiac depolarization;   escape interval timing means for timing an escape interval establishing a pacing rate and providing an escape interval pace trigger signal at the time out of the escape interval, the escape interval timing means further comprising reset means for restarting the timing of the escape interval in response to one of the right or left ventricular sensed event signals;   right ventricular pacing pulse output means coupled with said right ventricular lead means and selectively responsive to an applied pace trigger signal for generating and delivering a right ventricular pacing pulse to said right ventricular lead means to evoke a right ventricular depolarization;   left ventricular pacing pulse output means coupled with said left ventricular lead means and selectively responsive to an applied pace trigger signal for generating and delivering a left ventricular pacing pulse to said left ventricular lead means to evoke a left ventricular depolarization;   means for applying said escape interval pace trigger signal to one of said right ventricular pacing pulse output means or said left ventricular pacing pulse output means;   left ventricular conduction delay window timing means coupled with said escape interval timing means and said right ventricular depolarization sensing means for timing a left ventricular conduction delay window from a right ventricular sensed event signal and selectively from an escape interval pace trigger signal and for providing a left ventricular pace trigger signal at the expiration of the left ventricular conduction delay window time, said left ventricular conduction delay window timing means further coupled with said left ventricular depolarization sensing means and comprising left ventricular window terminating means for terminating the timing out of the left ventricular conduction delay window in response to a left ventricular sensed event signal;   means for applying said left ventricular pace trigger signal to said left ventricular pacing pulse output means as a pace trigger signal for triggering the generation and delivery of a left ventricular pacing pulse to said left ventricular lead means;   right ventricular conduction delay window timing means coupled with said escape interval timing means and said left ventricular depolarization sensing means for timing a right ventricular conduction delay window from a left ventricular sensed event signal and selectively from an escape interval pace trigger signal and for providing a right ventricular pace trigger signal at the expiration of the right ventricular conduction delay window time, said right ventricular conduction delay window timing means further coupled with said right ventricular depolarization sensing means and comprising right ventricular window terminating means for terminating the timing out of the right ventricular conduction delay window in response to a right ventricular sensed event signal; and   means for applying said right ventricular pace trigger signal to said right ventricular pacing pulse output means as a pace trigger signal for triggering the generation and delivery of a right ventricular pacing pulse to said right ventricular lead means;   whereby an excessive conduction delay between a spontaneous or evoked depolarization in the right ventricle and the conducted depolarization wave in the left ventricular or an excessive conduction delay between a spontaneous or evoked depolarization in the left ventricle and the conducted depolarization wave in the right ventricle is corrected by generation and delivery of a pacing pulse to the left or right ventricle, respectively at the timing out of the corresponding conduction delay window.   
     
     
       2. The pacing system of claim 1, further comprising means for programming said left ventricular conduction delay window in a range of 0-100 msec. 
     
     
       3. The pacing system of claim 1, further comprising means for programming said right ventricular conduction delay window in a range of 0-100 msec. 
     
     
       4. The pacing system of claim 1, further comprising: means for preventing the sensing of spontaneous and evoked cardiac depolarizations in the right ventricle and the provision of a right ventricular sensed event signal in response thereto for the duration of a right ventricular blanking period in response to the generation of a ventricular pacing pulse; and   means for preventing the sensing of spontaneous and evoked cardiac depolarizations in the left ventricle and the provision of a left ventricular sensed event signal in response thereto for the duration of a left ventricular blanking period in response to the generation of a ventricular pacing pulse.   
     
     
       5. The pacing system of claim 4, further comprising means for programming said left ventricular conduction delay window in a range of 0-100 msec. 
     
     
       6. The pacing system of claim 4, further comprising means for programming said right ventricular conduction delay window in a range of 0-100 msec. 
     
     
       7. A pacing method for improving the hemodynamic efficiency of a sick heart suffering from conduction delays in conducting spontaneous or evoked depolarizations originating in one of the right or left ventricle to the other of the left or right ventricle comprising the steps of: locating first and second right ventricular pace/sense electrode in relation with the right ventricle;   locating first and second left ventricular pace/sense electrodes in relation with the left ventricle;   sensing spontaneous and evoked cardiac depolarizations in the right ventricle across said right ventricular pace/sense electrodes and providing a right ventricular sensed event signal;   sensing spontaneous and evoked cardiac depolarizations in the left ventricle across said left ventricular pace/sense electrodes and providing a left ventricular sensed event signal;   timing an escape interval establishing a pacing rate and providing an escape interval pace trigger signal at the time out of the escape interval;   restarting the timing of the escape interval in response to one of the right or left ventricular sensed event signals;   in response to the escape interval pace trigger signal, selectively triggering either right ventricular pacing pulse output means coupled with said right ventricular pace/sense electrodes to generate and deliver a right ventricular pacing pulse to said right ventricular pace/sense electrodes to evoke a right ventricular depolarization or left ventricular pacing pulse output means coupled with said left ventricular pace/sense electrodes to generate and deliver a left ventricular pacing pulse to said left ventricular lead means to evoke a left ventricular depolarization;   timing a left ventricular conduction delay window from a right ventricular sensed event signal or from generation of a right ventricular pacing pulse and providing a left ventricular pace trigger signal at the expiration of the left ventricular conduction delay window   terminating the timing out of the left ventricular conduction delay window in response to a left ventricular sensed event signal;   applying said left ventricular pace trigger signal to said left ventricular pacing pulse output means to trigger the generation and delivery of a left ventricular pacing pulse to said left ventricular lead means;   timing a right ventricular conduction delay window from a left ventricular sensed event signal or from generation of a left ventricular pacing pulse and providing a right ventricular pace trigger signal at the expiration of the right ventricular conduction delay window   terminating the timing out of the right ventricular conduction delay window in response to a right ventricular sensed event signal; and   applying said right ventricular pace trigger signal to said right ventricular pacing pulse output means to trigger the generation and delivery of a right ventricular pacing pulse to said right ventricular lead means;   whereby an excessive conduction delay between a spontaneous or evoked depolarization in one of the right or left ventricle and the conducted depolarization wave in the other of the left or right ventricle is corrected by generation and delivery of a pacing pulse at the timing out of the conduction delay window.   
     
     
       8. The pacing method of claim 7, further comprising the steps of: programming said left ventricular conduction delay window in a range of 0-100 msec; and   programming said right ventricular conduction delay window in a range of 0-100 msec.   
     
     
       9. The pacing method of claim 7, further comprising the steps of: preventing the sensing of spontaneous and evoked cardiac depolarizations in the right ventricle and the provision of a right ventricular sensed event signal in response thereto for the duration of a right ventricular blanking period in response to the generation of a ventricular pacing pulse; and   preventing the sensing of spontaneous and evoked cardiac depolarizations in the left ventricle and the provision of a left ventricular sensed event signal in response thereto for the duration of a left ventricular blanking period in response to the generation of a ventricular pacing pulse.   
     
     
       10. The pacing method of claim 9, further comprising the steps of: programming said left ventricular conduction delay window in a range of 0-100 msec; and   programming said right ventricular conduction delay window in a range of 0-100 msec.   
     
     
       11. A pacing method for improving the hemodynamic efficiency of a sick heart suffering from conduction delays in conducting spontaneous or evoked depolarizations originating in the right ventricle to the left ventricle comprising the steps of: locating first and second right ventricular pace/sense electrode in relation with the right ventricle;   locating first and second left ventricular pace/sense electrodes in relation with the left ventricle;   sensing spontaneous and evoked cardiac depolarizations in the right ventricle across said right ventricular pace/sense electrodes and providing a right ventricular sensed event signal;   sensing spontaneous and evoked cardiac depolarizations in the left ventricle across said left ventricular pace/sense electrodes and providing a left ventricular sensed event signal;   timing an escape interval establishing a pacing rate and providing an escape interval pace trigger signal at the time out of the escape interval;   restarting the timing of the escape interval in response to the right ventricular sensed event signals;   in response to the escape interval pace trigger signal, triggering the right ventricular pacing pulse output means coupled with said right ventricular pace/sense electrodes to generate and deliver a right ventricular pacing pulse to said right ventricular pace/sense electrodes to evoke a right ventricular depolarization;   timing a left ventricular conduction delay window from a right ventricular sensed event signal or from generation of a right ventricular pacing pulse and providing a left ventricular pace trigger signal at the expiration of the left ventricular conduction delay window   terminating the timing out of the left ventricular conduction delay window in response to a left ventricular sensed event signal; and   applying said left ventricular pace trigger signal to said left ventricular pacing pulse output means to trigger the generation and delivery of a left ventricular pacing pulse to said left ventricular lead means;   whereby an excessive conduction delay between a spontaneous or evoked depolarization in the right ventricle and the conducted depolarization wave in the left ventricle is corrected by generation and delivery of a pacing pulse at the timing out of the conduction delay window.   
     
     
       12. The pacing method of claim 11, further comprising the step of: programming said left ventricular conduction delay window in a range of 0-100 msec.   
     
     
       13. The pacing method of claim 11, further comprising the steps of: preventing the sensing of spontaneous and evoked cardiac depolarizations in the right ventricle and the provision of a right ventricular sensed event signal in response thereto for the duration of a right ventricular blanking period in response to the generation of a ventricular pacing pulse; and   preventing the sensing of spontaneous and evoked cardiac depolarizations in the left ventricle and the provision of a left ventricular sensed event signal in response thereto for the duration of a left ventricular blanking period in response to the generation of a ventricular pacing pulse.   
     
     
       14. The pacing method of claim 13, further comprising the step of: programming said left ventricular conduction delay window in a range of 0-100 msec.   
     
     
       15. A pacing system for improving the hemodynamic efficiency of a sick heart suffering from conduction delays in conducting spontaneous or evoked depolarizations originating in the right ventricle to the left ventricle comprising: right ventricular lead means for locating first and second right ventricular pace/sense electrode in relation with the right ventricle;   left ventricular lead means for locating first and second left ventricular pace/sense electrodes in relation with the left ventricle;   right heart sensing means for sensing spontaneous and evoked cardiac depolarizations in the right ventricle across said right ventricular pace/sense electrodes and providing a right ventricular sensed event signal;   left heart sensing means for sensing spontaneous and evoked cardiac depolarizations in the left ventricle across said left ventricular pace/sense electrodes and providing a left ventricular sensed event signal;   escape interval timing means for timing an escape interval establishing a pacing rate and providing an escape interval pace trigger signal at the time out of the escape interval;   reset means for restarting the timing of the escape interval in response to the right ventricular sensed event signals;   right ventricular pacing pulse output means coupled with said right ventricular pace/sense electrodes responsive to the escape interval pace trigger signal for generating and delivering a right ventricular pacing pulse to said right ventricular pace/sense electrodes to evoke a right ventricular depolarization;   means for timing a left ventricular conduction delay window from a right ventricular sensed event signal or from generation of a right ventricular pacing pulse and providing a left ventricular pace trigger signal at the expiration of the left ventricular conduction delay window   means for terminating the timing out of the left ventricular conduction delay window in response to a left ventricular sensed event signal; and   left ventricular pacing pulse output means coupled with said left ventricular pace/sense electrodes and responsive to said left ventricular pace trigger signal for generating and delivering a left ventricular pacing pulse to said left ventricular lead means;   whereby an excessive conduction delay between a spontaneous or evoked depolarization in the right ventricle and the conducted depolarization wave in the left ventricle is corrected by generation and delivery of a pacing pulse at the timing out of the conduction delay window.   
     
     
       16. The pacing system of claim 15, further comprising means for programming said left ventricular conduction delay window in a range of 0-100 msec. 
     
     
       17. The pacing system of claim 15, further comprising: means for preventing the sensing of spontaneous and evoked cardiac depolarizations in the right ventricle and the provision of a right ventricular sensed event signal in response thereto for the duration of a right ventricular blanking period in response to the generation of a ventricular pacing pulse; and   means for preventing the sensing of spontaneous and evoked cardiac depolarizations in the left ventricle and the provision of a left ventricular sensed event signal in response thereto for the duration of a left ventricular blanking period in response to the generation of a ventricular pacing pulse.   
     
     
       18. The pacing system of claim 17, further comprising means for programming said left ventricular conduction delay window in a range of 0-100 msec.